AR films are often constructed of alternating high and low refractive index (“RI”) polymer layers of the correct optical thickness. With regards to visible light, this thickness is on the order of one-quarter of the wavelength of the light to be reflected. The human eye is most sensitive to light around 550 nm. Therefore it is desirable to design the low and high index coating thicknesses in a manner that minimizes the amount of reflected light in this optical range (e.g. 2.5% or lower).
U.S. Pat. No. 7,264,872 describes a durable high index nanocomposite for antireflective coatings. The high refractive nanocomposite comprises surface modified inorganic nanoparticles, such as zirconia, dispersed in a crosslinked organic material.